Grease pencil

More recently, it has been produced in propelling form, essentially similar to a mechanical pencil, this type in particular being associated with knee boards employed by NATO aircrew.

Surfaces used with grease pencils include glass, rock, polished stone, plastic, ceramics, acetate, and other glazed, lacquered or polished surfaces, and metal, as well as the glossy paper that is used for photographic printing (particularly for contact sheets), x-rays, maps, and for marking edits on analog audio tape and film.

[2] As information came in from radar and radio operators, technicians would take details of aircraft locations, vectors, weapons and fuel status and other information and write it in reverse on a large, clear panel of glass, which was readable to the officers on the other side of the panel.

[citation needed] In the days when broadcast studios had a library of LP records, a track which was prohibited from public performance could be defaced by a wavy white or yellow chinagraph line, giving a visible warning to the presenter as well as making that track unusable.

[citation needed] Grease pencils are also commonly used by fire brigades in the United Kingdom.